mpd.lua

   1 #!/usr/bin/lua
   2
   3 function url_decode(str)
   4   if not str then return nil end
   5   str = string.gsub (str, "+", " ")
   6   str = string.gsub (str, "%%(%x%x)", function(h) return
   7     string.char(tonumber(h,16)) end)
   8   str = string.gsub (str, "\r\n", "\n")
   9   return str
  10 end
  11
  12 function split(s, delimiter)
  13     local result = {};
  14     for match in (s..delimiter):gmatch("(.-)"..delimiter) do
  15         result[#result+1] = match;
  16     end
  17     return result;
  18 end
  19
  20 function string.starts(String,Start)
  21    return string.sub(String,1,string.len(Start))==Start
  22 end
  23
  24 function process_playlist(playlist)
  25   local res={}
  26   for _,record in pairs(playlist) do
  27     local splitted = split(record,": ")
  28     local name = splitted[2]
  29     local splitted = split(splitted[1],":")
  30     local id = splitted[1]
  31     local rectype = splitted[2]
  32     local rec = {}
  33     if not (id == "OK") then
  34       rec["id"] = id
  35       rec["type"] = rectype
  36       rec["name"] = name
  37       res[id] = rec
  38     end
  39   end
  40   return res
  41 end
  42
  43 function process_playlists(playlists)
  44   local res={}
  45   for _,record in pairs(playlists) do
  46     local splitted = split(record,": ")
  47     if splitted[1]=="playlist" then
  48       res[#res+1] = splitted[2]
  49     end
  50   end
  51   return res
  52 end
  53
  54 function process_directory(directory)
  55   local res={}
  56   for _,record in pairs(directory) do
  57     local splitted = split(record,": ")
  58     if splitted[1]=="directory" or splitted[1]=="file" then
  59       local rec={}
  60       rec["type"] = splitted[1]
  61       rec["name"] = splitted[2]
  62       res[#res+1] = rec
  63     end
  64   end
  65   return res
  66 end
  67
  68 require "uci"
  69 require("socket")
  70
  71 function mpd_new(settings)
  72     local client = {}
  73     if settings == nil then settings = {} end
  74
  75     client.hostname = settings.hostname or "localhost"
  76     client.port     = settings.port or 6600
  77     client.desc     = settings.desc or client.hostname
  78     client.password = settings.password
  79     client.timeout  = settings.timeout or 1
  80     client.retry    = settings.retry or 60
  81
  82     return client
  83 end
  84
  85
  86 function mpd_send(mpd,action,raw)
  87
  88     local command = string.format("%s\n", action)
  89     local values = {}
  90
  91     -- connect to MPD server if not already done.
  92     if not mpd.connected then
  93         local now = os.time();
  94         if not mpd.last_try or (now - mpd.last_try) > mpd.retry then
  95             mpd.socket = socket.tcp()
  96             mpd.socket:settimeout(mpd.timeout, 't')
  97             mpd.last_try = os.time()
  98             mpd.connected = mpd.socket:connect(mpd.hostname, mpd.port)
  99             if not mpd.connected then
 100                 return { errormsg = "could not connect" }
 101             end
 102             mpd.last_error = nil
 103
 104             -- Read the server's hello message
 105             local line = mpd.socket:receive("*l")
 106             if not line:match("^OK MPD") then -- Invalid hello message?
 107                 mpd.connected = false
 108                 return { errormsg = string.format("invalid hello message: %s", line) }
 109             else
 110                 _, _, mpd.version = string.find(line, "^OK MPD ([0-9.]+)")
 111             end
 112
 113             -- send the password if needed
 114             if mpd.password then
 115                 local rsp = mpd_send(mpd,string.format("password %s", mpd.password))
 116                 if rsp.errormsg then
 117                     return rsp
 118                 end
 119             end
 120         else
 121             local retry_sec = mpd.retry - (now - mpd.last_try)
 122             return { errormsg = string.format("%s (retrying in %d sec)", mpd.last_error, retry_sec) }
 123         end
 124     end
 125
 126     mpd.socket:send(command)
 127
 128     local line = ""; err=0
 129     while not line:match("^OK$") do
 130         line, err = mpd.socket:receive("*l")
 131         if not line then -- closed,timeout (mpd killed?)
 132             mpd.last_error = err
 133             mpd.connected = false
 134             mpd.socket:close()
 135             return mpd_send(mpd,action)
 136         end
 137
 138         if line:match("^ACK") then
 139             return { errormsg = line }
 140         end
 141
 142         if not raw then
 143
 144           local pattern = string.format("(%s)", ": ")
 145           local i = string.find (line, pattern, 0)
 146
 147           if i ~= nil then
 148               local key=string.sub(line,1,i-1)
 149               local value=string.sub(line,i+2,-1)
 150               values[string.lower(key)] = value
 151           end
 152
 153         else
 154
 155           values[#values+1]=line
 156
 157         end
 158     end
 159
 160     return values
 161 end
 162
 163
 164 json=require("json")
 165
 166 x = uci.cursor()
 167 settings = {}
 168 settings['host'] = x.get("mpd","server","host") or "localhost"
 169 settings['port'] = x.get("mpd","server","port") or 6600
 170 password = x.get("mpd","server","password")
 171 if password then
 172   settings["password"] = password
 173 end
 174
 175 m = mpd_new(settings)
 176
 177 command = url_decode(os.getenv('QUERY_STRING'))
 178
 179 if not command or command=="" then
 180   command="status"
 181 end
 182
 183 if command=="play" or command=="pause" or command=="stop" or command=="previous" or command=="next" then
 184   res=mpd_send(m,command)
 185 elseif command=="vold" then
 186   status=mpd_send(m,"status")
 187   volume=tonumber(status["volume"])
 188   res=mpd_send(m,"setvol "..(volume-3))
 189 elseif command=="volu" then
 190   status=mpd_send(m,"status")
 191   volume=tonumber(status["volume"])
 192   res=mpd_send(m,"setvol "..(volume+3))
 193 elseif command=="status" then
 194   res=mpd_send(m,"status")
 195   song=res["song"]
 196   playlist=mpd_send(m,"playlist",1)
 197   pl=process_playlist(playlist)
 198   if song then
 199     res['current_playing']=pl[song]['name']
 200   else
 201     res['current_playing']="No songs selected"
 202   end
 203 elseif command=="playlist" then
 204   playlist=mpd_send(m,"playlist",1)
 205   res=process_playlist(playlist)
 206 elseif command=="repeat" then
 207   status=mpd_send(m,"status")
 208   rep=1-status["repeat"]
 209   res=mpd_send(m,"repeat "..rep)
 210 elseif string.starts(command,"cpl") then
 211   cmd=split(command,"|")
 212   id=cmd[3]
 213   command=cmd[2]
 214   if command=="playitem" then
 215     command="play "..id
 216     res=mpd_send(m,command)
 217   end
 218   if command=="clear" then
 219     res=mpd_send(m,"clear")
 220   end
 221   if command=="remove" then
 222     command="delete "..id
 223     res=mpd_send(m,command)
 224   end
 225   if command=="moveup" then
 226     command="swap "..id.." "..(id-1)
 227     res=mpd_send(m,command)
 228   end
 229   if command=="movedown" then
 230     command="swap "..id.." "..(id+1)
 231     res=mpd_send(m,command)
 232   end
 233 elseif string.starts(command,"lists") then
 234   cmd=split(command,"|")
 235   command=cmd[2]
 236   if command=="load" then
 237     if not cmd[3] then
 238       lists=mpd_send(m,"listplaylists",1)
 239       res=process_playlists(lists)
 240     else
 241       res=mpd_send(m,"load "..cmd[3],1)
 242     end
 243   end
 244   if command=="save" and cmd[3] then
 245     res=mpd_send(m,"save "..cmd[3],1)
 246   end
 247   if command=="delete" and cmd[3] then
 248     res=mpd_send(m,"rm "..cmd[3],1)
 249   end
 250   if command=="edit" then
 251     if cmd[3] then
 252       dir=mpd_send(m,"lsinfo \""..cmd[3].."\"",1)
 253     else
 254       dir=mpd_send(m,"lsinfo",1)
 255     end
 256     res=process_directory(dir)
 257   end
 258   if command=="add" then
 259     res={}
 260     if cmd[3] then
 261       res=mpd_send(m,"add \""..cmd[3].."\"")
 262     end
 263   end
 264 end
 265
 266 if not res then
 267   print("Content-Type: text/plain\r\n")
 268   print("MPD server - unknown command "..command)
 269 elseif (res['error_msg']) then
 270   print("Content-Type: text/plain\r\n")
 271   print("MPD server connection error: "..res['error_msg'])
 272 else
 273   print "Content-Type: text/plain\r\n"
 274   print(json.encode(res))
 275 end